Tool for reshaping metal tubular articles



June 13, 1967 w. E. SHULTZ 3,324,701

TOOL FOR RESHAPING METAL TUBULAR ARTICLES Filed Sept. 10, 1964 INVENTOR WILLIAM 5.8 ULTZ QM M97 United States Patent 3,324,701 TOOL FOR RESHAPING METAL TUBULAR ARTICLES William E. Shultz, 239 N. Main St., Lombard, 111. 60148 Filed Sept. 10, 1964, Ser. No. 395,439 3 Claims. c1. 72-393 This invention relates to a hand tool for reshaping and restoring damaged or deformed tubular stock such, for example, as the piping of automobile type exhaust systems as well as upper and lower automobile radiator necks.

A hand tool for reshaping tubular stock in accordance with this invention is of such construction and design as to enable a mechanic to perform the work of reshaping and restoring deformed exhaust piping of automobile installations from a position underneath the automobile.

It is an object of this invention to provide a tool of the character indicated which will be comparatively simple in construction and assembly, strong, durable, highly efficient and reliable in use, compact and adapted to be manufactured at low cost.

All of the foregoing and still further objects and advantages of the invention will become apparent from a study of the following specification, taken in connection with the accompanying drawings wherein like characters of reference designate corresponding parts throughout the several views, and wherein:

FIG. 1 is a cross sectional view, with portions in elevation, illustrating a tool embodying the features of this invention as the same appears when the tool is adjusted to a partially expanded condition.

FIG. 2 is an end view of the tool as seen from the front end of the tool as shown in FIG. 1.

FIG. 3 is an end view of the tool as it appears when in non-expanded state.

FIG. 4 is a side view of the tool as it appears when in non-expanded state.

FIG. 5 is a detail elevational view of one of the spreader segments.

FIG. 6 is a sectional view taken along line 66 of FIG. 4.

In the form of device chosen for the purpose of illustrating the construction and operation of a hand tool embodying the features of the present invention, there is provided a central threaded spindle or shaft 10 and a handle 11 having an internally threaded axial bore 12 into which the shaft 10 is threadedly received for movement between advanced and retracted position relative to the handle along a line of travel extending axially of said handle in response to rotation of the handle relative to the shaft 10. A wedge shaped cam member, designated generally by the reference numberal 13 is internally threaded for engagement with the threaded forward end of the shaft 10 and a lock screw 14 extending through a threaded opening in the cam member 13 has tight engagement with the portion of the shaft 10 in axial alignment therewith to thereby establish a fixed connection between the cam member 13 and the shaft 10 to provide for movement of the cam member 13 in unison with the shaft 10. Rearward movement of the shaft 10 relative to the handle 11 is limited by the inner surface of a forwardly open recess 14 provided in a collar 15 through which the portion of the shaft 10 between the cam member 13 and the handle 11 extends. It will be observed from the drawings that cam member 13 is provided with a series of six duplicate faces 16 which correspond to the faces of a hexagonally based pyramid with the faces extending in uniformly diverging relation in a direction away from the handle 11. The faces 16 3,324,701 Patented June 13, 1967 accordingly provide rearwardly and radially inwardly sloping surfaces in the direction of the handle 11 on which a corresponding number of separate duplicate spreader segments 17 have face to face sliding engagement via sloped surfaces 18 on said segments complementary to the face 16 of the cam member opposite thereto, as the handle member 11 is rotated to move the shaft 10 between retracted and advanced positions as shown in FIGS. 1 and 4 respectively. Such supporting engagement between the segments 17 and the cam member 13 is established via flexible retainers or elastic rings 19 collectively encircling the segments 17 as shown in FIGS. 1 and 4, thereby maintaining said segment 17 in a cluster about said cam member 13 with a segment opposite each of the faces of the cam member. Each segment 17 is provided with grooves 20 along lines in radial alignment with planes at right angles to the axis of the shaft 10. The grooves 20 and the retainers 19 are so dimensioned as to allow the retainers 19 to occupy a nested position within the confines of the outer surfaces of the segments at opposite sides of the grooves. While the segments 17 are thus collectively maintained in a cluster about the cam members 13, the segments have axially rearward engagement with front facing surfaces of the collar 15 so as to fix the axial position of said segments relative to the shaft 10. The portion of the handle 11 immediately adjoining the rear face of the collar 15 is provided with a radially extending guard plate 21. This guard plate is effective to protect the operators hand from injury while the hand is flexed about the handle member 11 and axial forward thrust is applied on the tool for insertion into the end of a tubular work piece to be reshaped with the aid of the tool.

For the purpose of maintaining the segments in a line of travel coincident with a fixed plane containing the axis of the cam member 13 and shaft 10 during radially expanding and contracting movements of the segments, each face 16 of the cam member 13 is provided with a central groove 22 defining a guideway in which a rib 23 on the surface of the segment 17 opposite thereto has interfitting sliding engagement.

It will be noted that the outwardly facing surface of each segment 17 is of arcuate cross-sectional contour in planes perpendicular to the axis of the cam member 13 while each segment is of forwardly tapered contour in planes containing said axis of the cam member at the leading end thereof. Outer surface portions of each segment extending rearwardly from and merging smoothly with said leading end extend along lines parallel to the axis of the cam member to define the area of maximum radial dimension of said segments as conforming substantially to a cylinder concentric with the axis of the cam member. Thus the leading end of the segments 17 may be adjusted to a part of less diameter than the internal dimension of the tubular stock to be reshaped with the aid of the tool. At such time as the leading end of the segments 17 thus reach an inserted position in the tubular stock undergoing work wherein the area of maximum radial dimension is likewise less than the internal dimension of the stock, the handle is operable by turning in a direction to retract the cam member 13 toward the handle to establish a wedging action between the segments 17 and the internal surface of the tubular stock opposite thereto. Havin-g established such wedging action, the tool is thereupon forced further into the tubular stock by the application of blows of a hammer against the rear end of the handle. While accordingly driving the segments 17 a desired distance into the tubular stock, as permitted by the hand guard 21, the stock is bulged sufficiently to reshape and straighten any deformities in the surface thereof with which the segments 17 have engagement.

It is believed that the many advantages of a tool constructed in accordance with the present invention will be readily understood and although a preferred embodiment of the device is as illustrated and described, it is to be understood that changes in the details of construction and in the combination and arrangement of parts may be resorted to which will fall within the scope of the invention as claimed.

What is claimed is:

1. A tool for reshaping and restoring damaged and deformed metal tubular stock, said tool including a plurality of spreader segments of duplicate size and shape, a shaft having a threaded portion at one end thereof and a portion at its other end defining a cam member having a number of du licate faces matching the number of said spreader segments, said faces corresponding to the faces of a pyramid in axial alignment with and diverging in a direction away from said threaded portion of said shaft, means for flexibly retaining said spreader segments, one to each face of the cam, in a cluster about said cam while allowing sliding engagement of said segments with surfaces of the faces of the cam opposite thereto in response to axial movement of the shaft relative to said segments, and means for effecting axial movement of the shaft relative to said segments and for thereby causing the segments to be moved radially outwardly of the axis of said shaft and cam into wedging engagement with the internal surface of a tubular stock to which said tool is operatively applied, said means including a handle having an internal threaded bore in which said threaded portion of the shaft has threaded engagement and a collar fixed to said handle through which the shaft extends for free turning movement and with which collar said segments have rearward engagement, said handle providing a member about which the hand of a person operating the tool may be comfortably flexed in gripping relation to said handle and having a rear end for receiving impacts of a hammer or the like to apply axial forward thrust on said segments while said segments have wedging engagement with said tubular stock, and a radially extending guard between said collar and said guard.

2. A tool according to claim 1 wherein complemental rib and groove formations on the cam faces and the faces of the segments opposite thereto cooperate to guide said segments along lines of travel parallel to the axis of the shaft while said segments undergo movement between varying radial positions.

3. A tool according to claim 1 wherein grooves formed in each segment in spaced apart relation axially of said shaft cooperate to provide a series of continuous grooves circumferentially of the tool in planes extending radially of said shaft, and means for flexibly retaining said spreader segments in a cluster about said cam include resilient rings confined in said continuous grooves in depressed relation to surfaces of said spreader segments at opposite sides of said grooves.

References Cited UNITED STATES PATENTS 1,346,957 7/1920 Hansen 72393 1,476,983 12/1923 King 72393 1,705,843 3/1929 Walter 72--392 2,442,965 6/1948 Thomas 72303 2,672,175 3/1959 'Howard 72393 CHARLES W. LANHAM, Primary Examiner.

RICHARD J. HERBST, Examiner. 

1. A TOOL FOR RESHAPING AND RESTORING DAMAGED AND DEFORMED METAL TUBULAR STOCK, SAID TOOL INCLUDING A PLURALITY OF SPREADER SEGMENTS OF DUPLICATE SIZE AND SHAPE, A SHAFT HAVING A THREADED PORTION AT ONE END THEREOF AND A PORTION AT ITS OTHER END DEFINING A CAM MEMBER HAVING A NUMBER OF DUPLICATE FACES MATCHING THE NUMBER OF SAID SPREADER SEGMENTS, SAID FACES CORRESPONDING TO THE FACES OF A PYRAMID IN AXIAL ALIGNMENT WITH AND DIVERGING IN A DIRECTION AWAY FROM SAID THREADED PORTION OF SAID SHAFT, MEANS FOR FLEXIBLY RETAINING SAID SPREADER SEGMENTS, ONE TO EACH OTHER FACE OF THE CAM, IN A CLUSTER ABOUT SAID CAM WHILE ALLOWING SLIDING ENGAGEMENT OF SAID SEGMENTS WITH SURFACES OF THE FACES OF THE CAM OPPOSITE THERETO IN RESPONSE TO AXIAL MOVEMENT OF THE SHAFT RELATIVE TO SAID SEGMENTS, AND MEANS FOR EFFECTING AXIAL MOVEMENT OF THE SHAFT RELATIVE TO SAID SEGMENTS AND FOR THEREBY CAUSING THE SEGMENTS TO BE MOVED RADIALLY OUTWARDLY OF THE AXIS OF SAID SHAFT AND CAM INTO WEDGING ENGAGEMENT WITH THE INTERNAL SURFACE OF A TUBULAR STOCK TO WHICH SAID TOOL IS OPERATIVELY APPLIED, SAID MEANS INCLUDING A HANDLE HAVING AN INTERNAL THREADED BORE IN WHICH SAID THREADED PORTION OF THE SHAFT HAS THREADED ENGAGEMENT AND A COLLAR FIXED TO SAID HANDLE THROUGH WHICH COLLAR SAID FOR FREE TURNING MOVEMENT AND WITH WHICH COLLAR SAID SEGMENTS HAVE REARWARD ENGAGEMENT, SAID HANDLE PROVIDING A MEMBER ABOUT WHICH THE HAND OF A PERSON OPERATING THE TOOL MAY BE CONFORTABLY FLEXED IN GRIPPING RELATION TO SAID HANDLE AND HAVING A REAR END FOR RECEIVING IMPACTS OF A HAMMER OR THE LIKE TO APPLY AXIAL FORWARD THRUST ON SAID SEGMENTS WHILE SAID SEGMENTS HAVE WEDGING ENGAGEMENT WITH SAID TUBULAR STOCK, AND A RADIALLY EXTENDING GUARD BETWEEN SAID COLLAR AND SAID GUARD. 